It's not a difficult concept, even though the doctrine (like all doctrines) has its obscure moments, which can be explored in a CALI offering available to law school students and professors here.

But the basic concept of the Bill of Rights protecting individuals solely from government action tends to be forgotten in the context of the First Amendment. On too many occasions, when an argument between two people escalates so that one person over-talks the other, or says "shut up," or even kicks the other person off the show or blog, the "loser" cries a violation of the First Amendment. Even when the "loser" is someone who would ordinarily decry constitutional "interference" between individuals.

Most recently, Dr. Laura Schlessinger, whose racial epithets on her radio show have caused criticism, has announced her retirement from the show, reportedly claiming that she wants "to regain my First Amendment rights." Sarah Palin also invoked the First Amendment in two tweets: Dr.Laura:don’t retreat…reload! (Steps aside bc her 1st Amend.rights ceased 2exist thx 2activists trying 2silence”isn’t American,not fair”) Dr.Laura=even more powerful & effective w/out the shackles, so watch out Constitutional obstructionists. And b thankful 4 her voice,America!

Ken Paulson of The First Amendment Center has a clear and concise explanation of why this is not a First Amendment issue, including discussing state action, but also additional rejoinders to Dr. Laura Schlessinger's claims of being bullied by the left, as well as the problem of equating the marketplace of ideas with the marketplace.